Continuous Integration : GIT to trigger the Hudson build when code is pushed to a branch.

With the latest version of the Jenkins and Git plug-in this is quite easily doable using the notifyCommit feature of the Git Plug-in  but if someone is stuck with the older version of Hudson as in our case there are the workarounds.

Let's walk though  them step by step.

Step  1.

In the Hudson job, check option Trigger builds remotely (e.g., from scripts) in the Build Triggers

This URL can trigger the build remotely

Use the following URL to trigger build remotely: HUDSON_URL/job/JOB_NAME/build?token=TOKEN_NAME
or /buildWithParameters?token=TOKEN_NAME

If your Hudson server requires authentication   before triggering the build then you need to provide the user name and password with this URL , Hudson provides feature of using BASIC auth

See details http://wiki.hudson-ci.org/display/HUDSON/Authenticating+scripted+clients

Step  2.

Modify post update hook under your git repository

Location of hook <yourrepos.git>/hooks/post-update

This curl command will trigger the Hudson build

curl --user <hudsonuser>:<password> ‘HUDSON_URL/job/JOB_NAME/build?token=TOKEN_NAME '

e.g. this can be something like

curl --user myuser:mypass 'http://myhudson:8080/job/Git_trigger_job/build?token=authtoken'

Step  3.

Customize the post update hook to trigger the build only when changes are pushed to a specific branch.

#!/bin/bash # # An example hook script that is called after a successful # upadte is made. # # To enable this hook, rename this file to "post-update". echo in "post update hook" #next line fetches the branch name which got updated branch=$(git rev-parse --symbolic --abbrev-ref $1) echo Update pushed to branch $branch if [ $branch == "dev" ]; then    echo "dev branch updated" curl --user myuser:mypass 'http://myhudson:8080/job/Git_trigger_job/build?token=authtoken' elif [  $branch == "test" ]; then    echo "test script called "    # place your code to call any job when code pushed to the test branch elif [  $branch == "production" ]; then    echo "production script"     # place your code to call any job when code pushed to the production branch fi exec git update-server-info

Step 4 .
Testing it out

This is the output shown in git console whenever the branch is updated /pushed

git push --progress  origin dev Counting objects: 19, done. Compressing objects: 100% (9/9) Writing objects: 100% (10/10) Writing objects: 100% (10/10), 838 bytes, done. Total 10 (delta 3), reused 0 (delta 0) remote: in post update hook remote: Update pushed to branch dev remote: dev remote:   % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current remote:   0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0 remote:   0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0 To git@mygit:repos/myrepos.git a5b64bb..497b512  dev -> dev Success

And this will trigger the Hudson job